Wiper blades having different sizes for automobile glass panels

ABSTRACT

The invention relates to wiper blades of various dimensions for windows of motor vehicles, with band-like, elongated, spring-elastic support elements ( 14 ), each for a respective wiper strip ( 22 ), which is associated with each wiper blade ( 10 ), can be placed against the window ( 12 ), and is disposed on the lower band surface ( 21 ) oriented toward the window, where in a longitudinal midsection of each support element, the upper band surface ( 15 ) oriented away from the window supports a wiper blade half ( 16 ) of a connecting device ( 18 ). In order to supply wiper blades of different dimensions with a single type of such a connecting device half and to thereby reduce the costs for the wiper blades, the widths ( 36 ) of the support elements in this longitudinal midsection are the same size independent of the other dimensions of these support elements.

BACKGROUND OF THE INVENTION

In the design of wiper blades, a multitude of criteria predetermined bylawmakers and vehicle manufacturers must be taken into account, e.g. thewindow region to be wiped by the wiper blades, window size, windowcurvature, contact pressure of the wiper blades against the window,course of air flow in front of the window, etc. For obvious reasons,this results in the fact that specific support elements for the wiperstrips resting against the window are required for practically everyvehicle type and even for the wiper blade on the driver's side versusthe one on the passenger side. These support elements must then beprovided with the wiper blade half of a connecting device by means ofwhich the wiper blade can be connected to the wiper arm, which isequipped with the other half of the connecting device.

In this context, the effort to comply with specifications predeterminedby the vehicle manufacturer has yielded support elements that varyparticularly in terms of their different lengths and widths. Inaddition, in support elements of this kind, for example their width canalso vary over their length, where the cross section of the supportelement or its width tapers starting from the seat position of theconnecting device half. In known wiper blades of this type, DE19729865.6 A1), the device half engages the support element on its outerlongitudinal edges with hook-like projections so that it is affixed tothe support element. However, since for the above-mentioned reasons, themaximal width of the support element differs from case to case, for eachof these cases, a particular device half, which is adapted to the widthof the support element, must be kept on hand, even if the variations inwidth are relatively slight. This is because the device half mustalways, even during wiping operation, be connected to the supportelement so that it does not move lateral to the longitudinal directionof the wiper blade because of the other wiper blade half of theconnecting device.

This requirement causes a multitude of device halves to be requiredsince as a rule, each of these halves can be used for only one wiperblade of a single vehicle type.

Comparable problems arise in the two end sections of the supportelements, to which cap-like holders must be attached. These caps areintended, for example, to reduce the risk of injury presented by the endedges of the support elements during handling of the wiper blades, forexample when replacing them. In known wiper blades of this type (DE19802451.7 A1), these caps can also aid in the connection between thewiper strip and the support element if they engage the support element,for example with claws, and hold the wiper strip. It is also true ofthese caps and for their seat positions on the support elements that forthe reasons mentioned above, the width of the support elements at theirends varies in size from case to case. Therefore, correspondinglyadapted caps must also be produced for each different use, whichstarting with the manufacturing apparatuses for these caps, down to thestorage and the danger of mixing them up during installation, is verycost-intensive.

SUMMARY OF THE INVENTION

With the wiper blade according to the invention, by standardizing thewidth of the support elements in the above-mentioned longitudinalmidsection, at least several support element types can be provided withthe same device halves so that the manufacturing costs for these halvesare reduced and the storage of them is simplified.

Since the wiper blade half of the connecting device embraces the tworemote outer longitudinal edges of each support element in aform-fitting manner with longitudinal shoulders, the immobility of theconnection between the halves of the connecting device and the supportelement is further improved.

The multitude of caps can be fundamentally reduced and consequently, thecosts for the wiper blade can be considerably reduced.

The above-described features have no influence on the support elementdesign because both in the longitudinal midsection and in the endsections of the support elements, they are continuously stiffened by theadd-on pieces positioned there, which already has to be approximatelytaken into consideration in their dimensioning.

A proper fit of the caps on the support element ends is achieved if thecaps embrace the two remote outer longitudinal edges of each of thesupport element in a form-fitting manner with longitudinal shoulders.

In certain application instances, it is advantageous if the supportelements are embodied as one-piece bands, which have the same width inthe vicinity of the seat position of the device halves.

With a width of the support elements that exceeds a particular fitmeasurement in its effective spring regions, it is useful if the widthof the seat position is constituted by a partial, lateral constrictionof the support element.

However if the support element design falls below the width fitmeasurement predetermined for the support element, then the width of theseat position can be simply constituted by a partial, lateral wideningof the support element.

If the length of the constriction is matched to the length of the wiperblade device half, then an exactly determined seat position for thedevice half is achieved without having to carry out other measures.

For certain application instances, it is advantageous if the supportelements are embodied as one-piece bands, which have the same width inthe vicinity of the seat position of the cap.

In order to adapt the fit measurement of the support element width inthe vicinity of the seat positions of the caps, the fit measurement canbe maintained as a function of the respective width determined by thesupport element design by virtue of the fact that the width of the seatposition for the caps is determined by a partial lateral constriction ofthe support element or the width of the seat position for the caps isdetermined by a partial lateral widening of the support element.

The embodiment of the support elements by means of two spring strips,which are disposed parallel to and spaced apart from each other, can inmany application instances represent an advantageous alternative to theone-piece support elements.

In this connection, these spring strips that comprise a single supportelement can be disposed in longitudinal grooves in the wiper strip,which are disposed in a common plane spaced apart from the window andwhose bases are spaced apart from each other.

Other advantageous improvements and embodiments of the invention aredisclosed in the following description of exemplary embodiments shown inthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a side view of a wiper blade according to a firstembodiment of the invention,

FIG. 2 shows a top view of the wiper blade according to FIG. 1, enlargedand rotated by 90°,

FIG. 3 shows the sectional plane of a section through the wiper bladealong the line III—III in FIG. 2, enlarged and rotated by 90°,

FIG. 4 shows the sectional plane of a section through the wiper bladealong the line IV—IV in FIG. 2, enlarged and rotated by 90°,

FIG. 5 shows a perspective, partial view of a differently embodied wiperblade according to the invention,

FIG. 6 shows the sectional plane of a section through the wiper bladeaccording to FIG. 5, along the line VI—VI, rotated correspondingly,

FIG. 7 shows the sectional plane of a section through the wiper bladeaccording to FIG. 5, along the line VII—VII, rotated correspondingly,

FIGS. 8 to 10 show top views of differently designed support elements,which belong to the wiper blade according to FIGS. 1 to 4, and

FIGS. 11 to 13 show top views of differently designed support elements,which belong to the wiper blade according to FIGS. 8 to 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A wiper blade 10 for windows 12 of motor vehicles shown in FIGS. 1 and 2has an elongated spring-elastic support element 14. On the top side 15of the support element 14 oriented away from the window 12 to be wiped,the wiper blade half 16 of a connecting device 18 is disposed, with theaid of which the wiper blade 10 can be detachably connected to a drivenwiper arm 20, which is indicated with dot-and-dash lines in FIG. 1 andis guided on the body of a motor vehicle. On the underside 21 of thesupport element 14 oriented toward the window 12, an elongatedrubber-elastic wiper strip 22 is disposed with its longitudinal axisparallel to the support element. The wiper arm 20 and therefore also thewiper blade 10 are loaded in the direction of an arrow 24 toward thewindow to be wiped, whose surface to be wiped is indicated in FIG. 1 bya dot-and-dash line 26. Since the dot-and-dash line 26 is intended torepresent the sharpest curvature of the window surface, it is clear thatthe curvature of the unloaded wiper blade 10, with its two ends restingagainst the window 12, is sharper than the maximal window curvature.With the contact pressure (arrow 24), the wiper blade 10 rests with itswiper strip 22 against the window surface 26 over its entire length. Asa result, a tension is built up in the band-like spring-elastic supportelement 24, which assures a proper contact of the wiper strip 22 againstthe motor vehicle window 12 over its entire length. FIGS. 1 and 2 alsoshown that a cap 28 is respectively disposed at the two ends of thewiper blade 10 and the function of this cap will be discussed in moredetail below.

The specific design of a first embodiment of the wiper blade accordingto the invention will be explained in detail below. As shown by thesection through the wiper blade in FIG. 3, the wiper blade half 16 ofthe connecting device 18 has a plate-like base 30, which is providedwith coupling means, not shown in detail, for the free end of the wiperarm 20. The base plate 30 has L-shaped projections 32 on itslongitudinal sides, with which their one L-legs 31, embrace the remoteouter longitudinal edges 34 of the support element 14 and with theirother L-legs 33, engage under the support element 14 and rest againstthe underside 21 of the support element 14. The distance 36 between thetwo insides of the one L-legs 31 oriented toward each other correspondsto a fit measurement, which the support clement 14 has where the half 16is positioned.

In the two exemplary embodiments of the invention given here, this seatposition of the half 16 is shown in the longitudinal midsection of thewiper blade and the support element 14. The term “longitudinalmidsection”, however, does prevent this seat position from also beinglocated close to one of the two end sections of the wiper blade and thesupport element or even from coinciding with one of the two end sectionsof the support element so that the half 16 also performs one of thefunctions of the caps 28.

In the exemplary embodiment according to FIGS. 1 to 4, the supportelement is embodied as a one-piece band. In the vicinity of the seatposition of the device half 16, the two longitudinal edges 34 extendessentially parallel to each other, thus producing a fit measurement 36that is constant over the entire seat position for the half 16. Sincethe distance between the two L-legs 31—which, considered in and ofthemselves, can be also be referred to as longitudinal shoulders thatcooperate with the longitudinal edges 34—are spaced apart at a distance36, which corresponds to the fit measurement, this produces a favorablysnug fit between the support element 14 and the half 16 in terms of theworking direction of the wiper blade 10 (double arrow 37 in FIG. 2).FIG. 3 also shows that the support element 14 of the wiper blade 10 isdisposed at a distance 38 from the window 12 to be wiped when the wiperblade 10 with its wiper strip 22 assumes its operating position inrelation to the window 12. Finally, FIG. 2 also shows that the width ofthe support element 14, starting from the seat position for the half 16,tapers towards its two ends. This can also be seen by comparing the fitmeasurement 36 for the seat position of the half 16 to a second fitmeasurement 40 for the caps 28 (FIG. 4). The caps 28 have an essentiallyU-shaped cross-section, whose U-base 42—just like the base plate 30 ofthe half 16—rests against the top side 15 of the support element 14oriented away from the window 12. The two U-legs 43 of the caps 28 arespaced apart from each other by a distance that corresponds to the fitmeasurement 40. At the free ends of the U-legs 43, the caps are providedwith claws 44 oriented toward each other, which engage in longitudinalgrooves 45 of the wiper strip 22. In the exemplary embodiment, the endsurface 47 of the wiper strip 22 oriented away from the window 12 isconnected to the underside 21 of the support element 14 by means of aglued connection. Since the glued connection is subjected to a high,constant, alternating stress during wiper operation, the caps disposedat the ends of the support element 14 contribute significantly to thesecuring of the glued connection between the wiper strip 22 and thesupport element 14 when they engage with their claws in the wiper strip.

As explained at the beginning, since the wiper blades of the entirearray of wiper blades offered by the manufacturer must have differentdimensions, an essential factor of the invention will be discussed indetail below for the above-explained exemplary embodiment of a wiperblade, in conjunction with FIGS. 8 to 10. It should be noted that thesupport elements 114 (FIG. 9), 214 (FIG. 8), and 314 (FIG. 10) depictedin these figures are not shown to scale, particularly in thelongitudinal direction, and therefore can in no way be taken for workingdrawings. Assuming that the support element 114 shown in FIG. 9corresponds in its contour to the support element 14 in FIG. 2, thenthis is preferably conceived for midsized wiper blades. It has a fitmeasurement 36 in the vicinity of the seat position 115 for the half 16of the connecting device 18. At its two end sections 116, whichrepresent the seat positions for the two caps 28, the width of thesupport element 114 corresponds to the fit measurement 40.

The embodiment of the support element 214 shown in FIG. 8 is as a ruleconceived for wiper blades that are wider and longer than the wiperblades that are used with the support element 114 (FIG. 9). Therefore,the support element 214 is wider in its two regions between the seatposition 215 for the half 16 and the two seat positions 216 for the caps28 than it is in the corresponding regions of the support element 114(FIG. 9). So that the same halves 16 can be used with this supportelement 214 as with the support element 115, this support element 214 isprovided with opposing constrictions 217 on its two longitudinal sidesin the vicinity of the seat position 215, whose lengths 218 are matchedto the length of the half 16. The depth of the constrictions 217 isdimensioned to produce the fit measurement 36 in the vicinity of theseat position 215. A corresponding embodiment is provided at both endsof the support element 214. Constrictions 219 of the support element 214are also provided at these two ends to produce a width there in thevicinity of the seat positions 216 of the caps 28, which corresponds tothe fit measurement 40 so that wiper blades with a support element 214according to FIG. 8 can use not only the halves 16 but also the caps 28that are also used in wiper blades with a support element according toFIG. 9.

Considering the explanations made of the beginning, the support element314 according to FIG. 10 is preferably conceived for wiper blades thatare smaller than the wiper blades in which the support elements 114 and214 according to FIGS. 9 and 8 are used. However, so that the samehalves 16 that are used with the support elements 114 and 214 can beused here, this support element 314 is provided with partial lateralwidenings 317 on its two longitudinal sides in the vicinity of the seatposition 315 for the half 16. The widenings 317 on both sides of thesupport element 314 in the vicinity of the seat position 315 of the half16 are dimensioned to produce a width of the support element 314 there,whose size coincides with the fit measurement 36. It is thus possible touse the same halves 16 of the connecting device 18 for this supportelement 314 as for the support elements 114 and 214. In addition, thetwo end regions of the support element 314, which comprise the seatposition 316 for the holders 28, likewise have widenings 318 disposedopposite each other, which are dimensioned to produce a fit measurementin the vicinity of the seat positions 316 for the caps 28, whichcorresponds to the fit measurement 40 according to FIG. 4. It is thuspossible in wiper blades with support elements 314 according to FIG. 10to also use the same caps 28 that are used with the elements 114 and214.

As shown in FIGS. 5 to 7, another embodiment of the wiper blade 50according to the invention has a support element 55, which is divided inits longitudinal direction and consequently includes two spring strips56. This wiper blade 50 has a wiper strip 52, which, at a distance 53from the window 12, is provided with lateral, opposing longitudinalgrooves 54, which serve to contain the two spring strips 56 comprisingthe support element 55. In the exemplary embodiment, the two springstrips 56 are disposed in a common plane, but this is not absolutelynecessary. The bases of the two longitudinal grooves 54 are spaced apartfrom each other by a distance 57 (FIG. 6). The width of the two springstrips 56 is dimensioned so that they protrude with edge regions fromthe longitudinal grooves 54 containing them. This is particularlyimportant where the seat positions must be provided for the half 16 ofthe connecting device 18 and the caps 28. Since the wiper strip 52 inthis exemplary embodiment has a top strip 59 disposed on the top side 58of the support element 55, the half 16 must be provided with acorresponding receiving groove for the top strip 59. In this embodimentas well, on the longitudinal sides of a base plate 60 of the half 16,L-shaped projections 61 are provided, where the L-legs 62 cross theplane of the spring strips 56 and the other L-legs 63 engage under thesupport element 55 or its spring strips 56. The distance between theopposing L-legs 62 corresponds to a fit measurement 36, which iscomposed of the width of the spring strips 56 in the vicinity of theseat position for the cap 28 plus the measurement 57 between the twobases of the longitudinal grooves 54 (FIG. 6). In this embodiment (FIG.7), the caps have a design that corresponds to the design of the half 16according to FIG. 6. The longitudinal sides of a cap base plate 64 areadjoined by claw-like projections 65, which engage under the respectivespring strip 56. The distance between the two claws 65 in the vicinityof the spring strips 56 is dimensioned to produce a fit measurement 40,which is composed of the width of the two springs 56 in the vicinity ofthe two ends of the support element 55 plus the measurement 57 betweenthe two bases of the longitudinal grooves 54 that are spaced apart fromeach other. The fit measurement 40 is smaller than the fit measurement36 because the two spring strips 56, starting from the seat position forthe half 16, taper toward the seat positions for the caps 28. Since thewiper strip 52 is normally produced by means of the extrusion process,its cross sections are identical in the vicinity of the seat positionfor the half and also in the vicinities of the seat positions of thecaps. Consequently, the cap 28 must also be provided with a receivinggroove for the top strip 59.

FIGS. 11 to 13 showed different embodiments of the support element 55.The support element according to FIG. 12 is labeled with the referencenumeral 414. The embodiment of the support element according to FIG. 11has the reference numeral 514. FIG. 13 shows another embodiment of thesupport element, which is labeled with the reference numeral 614. Thesupport element 414 according to FIG. 12 has two spring strips 456,which are disposed parallel to each other and spaced apart from eachother by a distance that corresponds to the distance 57 (FIG. 6) betweenthe two bases of the longitudinal grooves 54 in the wiper strip 52. Thisalso applies for the spring strips 556 and 656 in the embodiments of thesupport elements 514 and 614 shown in FIGS. 11 and 13. Apart from thelongitudinal division of the support element in the exemplaryembodiments according to FIGS. 11 to 13, everything said about theembodiments according to FIGS. 8 to 10 (support elements 114, 214, and314) applies to the embodiments here. Thus, in the vicinity of the seatposition 415 for the half 16 of the connecting device 18, the supportelement 414 has a width that corresponds to the fit measurement 36. Inaddition, the width of the spring strips in the vicinity of the seatpositions 416 for the caps 28 is dimensioned to produce a fitmeasurement 40.

So that the wider support element 514 according to FIG. 11, in thevicinity of the seat position 515 for the half 16, can be matched to thefit measurement 36, constrictions 517 are likewise provided in thisvicinity on each of the spring strips 556, which correspond to theconstrictions 217 according to the support element 214 (FIG. 8). In thisinstance as well, the length of the constrictions 517 is matched to thelength of the half 16. The same is also true for the disposition anddesign of the two ends of the support element 514 in the vicinity of theseat positions 516 for the caps 28. Here, too, the correspondingconstrictions 519 are provided, which are dimensioned in order toproduce a fit measurement 40. In the embodiments according to FIGS. 11to 13, both the caps 28 and the half 16 assure a proper securing of thespring strips in the longitudinal grooves 54 of the wiper strip 52.

With the exception of the longitudinal division of the spring strips 656and the associated distance 57 between them, the embodiment of thesupport element according to FIG. 13 corresponds to the embodiment ofthe support element 314, which is shown in FIG. 10. In the vicinity ofthe seat position 615 for the half 16, each spring strip has anoutwardly directed widening 617 so that a fit measurement 36 is alsoprovided in this narrow support element 614. The same goes for theembodiment of the two ends of the support element 614. Correspondingwidenings 618 are also provided there so that a fit measurement 40 isproduced in the vicinity of the seat positions for the holders 28. Inthe embodiments according to FIGS. 11 to 13, both the caps 28 and thehalf 16 assure a proper securing of the spring strips in thelongitudinal grooves 54 of the wiper strip 52.

As explained above and also shown in the drawings, it goes withoutsaying that with all longitudinally divided support elements 414, 514,614, the distance 57 must be taken into consideration in thedimensioning of the fit measurement 36 and 40. It is consequently clearthat for both of the described embodiments according to FIGS. 1 to 4 and8 to 10, as well as FIGS. 5 to 7 and 11 to 13, through a correspondingembodiment of the support elements 114, 214, 314, and 414, 514, 614, thesame halves 16 of the connecting device 18 and the same holders 28 canbe used, even if the wiper blades have different dimensions,particularly in length and width. This is possible because the widths ofall of the support elements in the vicinity of these seat positions forthe halves and caps is the same size, independent of the otherdimensions of these support elements and of the wiper blades. It istherefore possible to operate a wide variety of wiper blades ofdifferent dimensions with a single type of connecting device halves andcaps.

What is claimed is:
 1. A wiper blade for windows of motor vehicles,comprising a band-like, elongated, spring-elastic support element curvedover a longitudinal extension of the support element, wherein thesupport element is defined by two ends and has two band surfaces,wherein on one of the band surfaces, a wiper strip that can be placed onthe windshield is arranged, whereby, a half of a connection device on aside of the wiper blade is disposed directly on the other band surfacein a longitudinal midsection of the support element, and wherein ends ofthe support are covered with caps, wherein the support element has seatpositions for the connection device and for the caps, wherein theconnection device and the caps have a U-shaped cross section with U-legsin the region of the seat positions, and wherein with the U-legs, theseat positions fittingly overlaps, and wherein on free ends of theU-legs, opposed claws are formed, wherein said claws under-engage thesupport element, wherein the width of the seat position for the half ofthe connection device is constituted by a partial lateral widening ofthe support element.
 2. A wiper blade according to claim 1 wherein thelength of the lateral widening is matched to the length of the wiperblade device half.